636542 has 4 divisors (see below), whose sum is σ = 954816. Its totient is φ = 318270.

The previous prime is 636541. The next prime is 636547. The reversal of 636542 is 245636.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 636542.

It is not an unprimeable number, because it can be changed into a prime (636541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159134 + ... + 159137.

It is an arithmetic number, because the mean of its divisors is an integer number (238704).

2⁶³⁶⁵⁴² is an apocalyptic number.

636542 is a deficient number, since it is larger than the sum of its proper divisors (318274).

636542 is a wasteful number, since it uses less digits than its factorization.

636542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318273.

The product of its digits is 4320, while the sum is 26.

The square root of 636542 is about 797.8358227104. The cubic root of 636542 is about 86.0218981554.

The spelling of 636542 in words is "six hundred thirty-six thousand, five hundred forty-two".